package com.example.tests;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import com.thoughtworks.xstream.XStream;

public class GroupDataGenerator {

	
	public static void main(String[] args) throws IOException {
	if (args.length < 3){
	System.out.println("please specify parameters <amount of test data> <file> <format>");
	return;
	}
	int amount = Integer.parseInt(args[0]);
	File file = new File(args[1]);
	String format = args[2];
	
	if (file.exists()){
		System.out.println("File " + file + " is already exists, please, remove it manually");
		return;
	}
	
	List<GroupData> groups = generateRandomGroups(amount);
	if ("csv".equals(format)){saveGroupsToCsvFile (groups, file);}
	else if ("xml".equals(format)){saveGroupsToXmlFile (groups, file);}
	else {System.out.println("Invalid format " + format);}
	
	}

	public static List<GroupData> loadGroupsFromCsvFile(File file) throws IOException {
		List<GroupData> list = new ArrayList<GroupData>();
		FileReader reader = new FileReader(file);
		BufferedReader bufferedReader = new BufferedReader(reader);
		String line = bufferedReader.readLine();
		while (line != null) {
			String[] part = line.split(",");
			GroupData group = new GroupData()
				.withName(part[0])
				.withHeader(part[1])
				.withFooter(part[2]);
			list.add(group);
			line = bufferedReader.readLine();
		}
		bufferedReader.close();
		return list;
	}
	
	private static void saveGroupsToCsvFile(List<GroupData> groups, File file) throws IOException {
	FileWriter writer = new FileWriter(file);
	for (GroupData group : groups) {
		writer.write(group.getName() + "," + group.getHeader()+ "," + group.getFooter() + ",!" + "\n");
	}
	writer.close();
	}

	private static void saveGroupsToXmlFile(List<GroupData> groups, File file) throws IOException {
	XStream xstream = new XStream();
	xstream.alias("group", GroupData.class);
	String xml = xstream.toXML(groups);
	FileWriter writer = new FileWriter(file);
	writer.write(xml);
	writer.close();
	}
		
	public static List<GroupData> loadGroupsFromXmlFile(File file){
		XStream xstream = new XStream();
		xstream.alias("group", GroupData.class);
		return (List<GroupData>) xstream.fromXML(file);
		}
	
	public static List<GroupData> generateRandomGroups(int amount) {
		List<GroupData> list = new ArrayList<GroupData>();
		for (int i = 0; i < amount; i++){
		GroupData group = new GroupData()
		.withName(generateRandomString())
		.withHeader(generateRandomString())
		.withFooter(generateRandomString());
		list.add(group);
		}
		return list;
	}
	
	
	public static String generateRandomString(){
		Random rnd = new Random();
		if (rnd.nextInt(3) == 0){
			return "";
			}
		else {return "test" + rnd.nextInt();}	
		}
	
	
}
